Method and apparatus for assembling parts

ABSTRACT

A method and an apparatus for fixing a part and a part support for mounting the part by use of adhesive via an intermediate member are disclosed. The adhesive is implemented by photocuring adhesive while the intermediate member is formed of a material transparent for light. The intermediate member is free from coloring and deformation when illuminated by light for curing the adhesive. The adhesive is prevented from dropping or turning round to other portions during assembly.

BACKGROUND OF THE INVENTION

[0001] The present invention relates to a method and an apparatus forassembling parts end more particularly to a method and an apparatus forfixing with adhesive a part and a part support for mounting the part viaan intermediate member or members provided between the part end the partsupport.

[0002] Generally, to fix a pert and a part support via a bracket-likeintermediate member positioned between the part and the part support, ithas been customary to fasten the part and part support and theintermediate member by using screws. Screws, however, are apt todisplace the part relative to the part support due to a torque when theyare driven, and thereby make it difficult to accurately position thepart.

[0003] In light of the above, the part and part support and theintermediate member may be so configured as to mate with each other in apreselected positional relation. Although this approach enhances thepositional accuracy of the individual structural element, it causes thepositional accuracy of the resulting assembly to be unconditionallydetermined by the finishing accuracy of the individual element. It istherefore necessary to machine the individual structural element withhigh accuracy. While this kind of approach reduces the assembling cost,it increases the material and machining costs of the individualstructural element. This is particularly true when the parts are plasticmoldings apt to scatter in accuracy due to sinking and other causes.

[0004] To assemble the part and part support via the intermediate memberwithout being effected by the finishing accuracy of the individualelement while maintaining them in on accurate positional accuracy, it isdesirable to connect the part, part support and intermediate member byusing adhesive. This, however, brings about a problem that whether ornot the part and part support are dislocated at the time of adhesiondetermines the positioning accuracy of the part relative to the partsupport after adhesion. It follows that the positional relation betweenthe part and the part support at the time of adhesion has criticalinfluence on the quality of the resulting product.

[0005] For example, assume that the above part is a print head includedin a printer, a line sensor included in a scanner, or a solid imagingdevice included in a CCD (Charge Coupled Device) camera. Then, when anypositional error occurs between the part and the part support, itdisplaces an image printed or read by the part and thereby deterioratesimage quality.

[0006] Particularly, when the part is an ink jet head included in an inkjet printer, it occurs that the distance between the head surface of thehead formed with nozzle holes and a recording medium is scattered orthat the nozzle holes fail to accurately face a position where an imageshould be printed on the recording medium. As a result, ink dropsejected from the nozzle holes reach the recording medium outside of apreselected printing position, noticeably lowering the image quality. Inthe case of a color printer including heads respectively loaded with inkof different colors (usually yellow ink, magenta ink, cyan ink and blackink), any positional error between the heads makes the print positionsof ink drops of different colors irregular. This brings the differentcolors forming a color image out of register or causes the color imageto distort.

[0007] The prerequisite with the adhesive scheme is therefore that thepart and the part support be accurately held, beforehand, in apreselected positional which will allow the part and part support toaccurately face an assembly position at the time of adhesion. In thisconnection, in the case of the head of a color printer, the allowableerror of the head adhered to the part support should be confined in therange of the order of microns.

[0008] As for the adhesive scheme, the positional relation between thepart and the part support at the time of adhesion is a critical factorthat determines the accuracy of mounting of the part to the partsupport, as stated earlier.

[0009] In light of the above, there has been proposed a part assemblingapparatus of the type positioning the part support at a preselectedposition and holding it there, while holding the part in a positionvariable relative to the part support. By varying the position of thepart, the apparatus adjusts a position in which the part should bemounted to the part support. An intermediate member is so positioned asto contact the part and part support. The apparatus applies photocuringadhesive to the interface between the part and the intermediate memberand the interface between the intermediate member and the part supportand the intermediate member for thereby fixing them together. This typeof apparatus, however, has the following problems left unsolved.

[0010] If light for curing the adhesive applied to the interfaces is notuniformly distributed, a part of the adhesive is rapidly cured while theother part is slowly cured. As a result, the thickness of the adhesivelayer differs from the part cured rapidly to the part cured slowly.Presumably, this is because the area of each interface ever which theadhesive applied sequentially increases with the elapse of time due to,e.g., the surface tension of the adhesive. The irregular thickness ofthe adhesive effects the positional relation between the structuralelements and thereby degrades the assembling accuracy of the structuralelements.

[0011] The above problem will be solved if the light is uniformlyradiated onto the adhesive. This, however, cannot be easily done becausethe gap available at the interface between the structural elements wherethe adhesive is applied is extremely small.

[0012] The intermediate member may be formed of resin transparent forlight, as al so proposed in the past. In this case, light is radiatedonto the interfaces of the intermediate member via the intermediatemembers, so that the adhesive existing at the interfaces is cured at asubstantially uniform rate. However, experiments showed that the lightdirectly illuminating the adhesive via the intermediate member causedthe composition of the transparent intermediate member to change andcaused the member to color in muddy yellow little by little. Thecoloring of the intermediate member was particularly conspicuous whenuse was made of UV (Ultra Violet) rays as the light and UV curableadhesive as the adhesive.

[0013] Further, because the UV transmission of such colored intermediatemember decreased, the UV rays could not fully cure the adhesive unlessradiated for more then the expected period of time via the intermediatemember, compared to the case of direct radiation. The decrease, in thecuring efficiency of the adhesive and therefore the extended radiationof the UV rays heated the intermediate member to such a degree that themember deformed.

[0014] In another conventional part assembling procedure, anintermediate member is positioned between the part and the part support.Adhesive is applied to a substantially vertical first interface and asubstantially horizontal second interface between the part and partsupport and the intermediate member, thereby connecting the part andpart support via the intermediate member. In this case, the adhesive isnot always applied to each interface to a preselected thickness over apreselected area although it may be fed in a preselected amount.Specifically, adhesive used to mount the part usually has relativelyhigh viscosity so as not to drop and is apt to protrude in the form ofyolk when applied to the surface of the part due to the surface tensionof the adhesive.

[0015] Assume that the structural members are assembled by the adhesiveprotruding from the surfaces of the members, as stated above. Then, itis likely that the area of the adhesive on each structure member issmaller than the expected adhering surface and causes the members tocome off due to short adhesion strength. In addition, when the thicknessof the adhesive differs from the first interface to the secondinterface, the structural members arc displaced from each other whenassembled. Moreover, the protuberance of the adhesive just afterapplication is not constant, rendering the stress inside of the adhesiveirregular during curing. Therefore, should the structural members beassembled without any processing following the application of theadhesive, the part would be inclined relative to the part support. Inaddition, it needs a long period of time for the adhesive protrudingfrom the adhering surfaces to be cured, resulting in low productivity.

[0016] Furthermore, the liquid-like adhesive applied to the firstinterface is apt to drop due to its own weight or to turn round to thesecond interface. When the adhesive drops or turns, round to any otherposition, the amount of the adhesive applied to the first interface andthat of the adhesive applied to the second interface differ from theinitial amount. As a result, the adhesive layers formed on the twointerfaces are different in thickness from each other.

[0017] In the above condition, the positional relations between the partand the intermediate member and between the part support and theintermediate member are quite likely to differ from the time of positionadjustment to the time of completion of the assembly. Errors in thiskind of positional relations cannot be corrected by the positionadjustment beforehand because the drop or the turn-round of the adhesiveor an increase or a decrease in the amount of the adhesive ascribablethereto cannot be estimated. By contrast, errors ascribable to thecontraction of the adhesive due to curing can be corrected by theposition adjustment beforehand because the positional deviation of theindividual member is proportional to the amount and area of applicationof the adhesive.

SUMMARY OF THE INVENTION

[0018] It is therefore an object of the present invention to provide amethod and an apparatus for assembling parts capable of preventing anintermediate member intervening between a part and a part support andformed of resin transparent for light from coloring or deforming whenilluminated by light for curing photocuring adhesive.

[0019] It is another object of the present invention to provide a methodand an apparatus for assembling parts capable of obviating shortadhesion strength and displacement during the adhesion of a part, a partsupport and an intermediate member and enhancing productivity at thetime of assembly.

[0020] It is a further object of the present invention to provide amethod and an apparatus for assembling parts capable of preventingadhesive from dropping or turning round to other port ions during theadhesion of a part, a part support, and an intermediate member.

[0021] In accordance with the present invention, a method of fixing apart and a part support for mounting the part by use of photocuringadhesive via an intermediate member formed of resin transparent forlight includes the steps of radiating light for curing the adhesive, andcutting a part of the light lying in a wavelength range causing theproperty of the intermediate member to change.

[0022] Also, in accordance with the present invention, an apparatus forfixing a part and a part support for mounting the part via anintermediate member formed of resin transparent for light and contactingthe part and part support includes an applying device for applyingphotocuring adhesive to interfaces between the part, part support andintermediate member, a radiating device for radiating light to theinterfaces via the intermediate member, and a bandpass filter positionedon an optical path for the light for cutting a part of the light lyingin a wavelength range causing the property of the intermediate member tochange.

[0023] Further, in accordance with the present invention, a method offixing a part and a part support for mounting the part via anintermediate member by using adhesive includes the steps of positioningthe intermediate member between the part and the part support, applyingadhesive to a substantially vertical first interface and a substantiallyhorizontal second interface between the part and the part support andthe intermediate member, causing a pressing device to press theintermediate member against the part and the part support, and causingthe adhesive applied to the first interface and second interface tospread.

[0024] Moreover, in accordance with the present invention, an apparatusfor fixing a part and a part support for mounting said part by usingadhesive with the intermediary of an intermediate member providedbetween the part and the part support includes a part support holdingportion for positioning and holding the part support at a preselectedassembling position. A part supporting portion supports the part in aposition adjustable relative to the part support held by the partsupport holding portion. A position detecting device detects theposition of the part supported by the part supporting portion. Aposition adjusting device adjusts, based on the position detected by theposition detecting device, a position in which the part should bemounted to the part support held by the part support holding device. Anadhesive applying device applies the adhesive to a substantiallyvertical first interface and a substantially horizontal second interfacebetween the part and the intermediate member and between the partsupport and said intermediate member. A pressing device presses theintermediate member against the part and part support to thereby causethe adhesive applied to the first interface and second interface tospread.

[0025] In addition, a method of fixing a part and a part support formounting the part via an intermediate member by using adhesive includesthe steps of positioning the intermediate member between the part andthe part support, applying adhesive to a substantially vertical firstinterface and a substantially horizontal second interface between thepart and the intermediate member and between the part support and saidintermediate member, and half-curing, before a relative position of thepart and the part support is adjusted, the adhesive applied to the firstinterface to a degree preventing the adhesive from dropping due to itsown weight.

BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The above and other objects, features and advantages of thepresent invention will become more apparent from the following detaileddescription taken with the accompanying drawings in which:

[0027]FIG. 1 is an external perspective view of a head unit assembled byan apparatus embodying the present invention;

[0028]FIG. 2 is a block diagram schematically showing the illustrativeembodiment;

[0029]FIG. 3 is a front view showing the general construction of theillustrative embodiment;

[0030]FIG. 4 is a perspective view showing the structural parts of thehead unit and a jig for conveying the parts to a preselected mountingposition;

[0031]FIGS. 5 and 6 are flowcharts demonstrating a specific operation ofthe illustrative embodiment;

[0032]FIG. 7 is a perspective view showing the jig positioned at asetting position defined on a set stage included in the illustrativeembodiment;

[0033]FIG. 8 is a perspective view showing a mechanism provided on anassembly stage included in the illustrative embodiment for positioningthe jig;

[0034]FIG. 9 is a perspective view showing a position adjusting unit foradjusting the position of the head surface of an ink jet head by holdingthe head;

[0035] FIGS. 10A-10C demonstrate a sequence of steps far causing headclamping means included in the position adjustment unit of FIG. 9 toclamp the ink jet head;

[0036]FIG. 11 is a perspective view of nozzle hole measuring meansincluded in the illustrative embodiment for detecting preselected threeof nozzle holes formed in the ink jet head;

[0037]FIG. 12 is a side elevation showing an intermediate membermounting unit for transferring intermediate members set on the jig to apreselected assembly position between a head support and the ink jethead, and adhesive applying means for applying UV (Ultra Violet) curableadhesive to the intermediate members;

[0038]FIGS. 13A and 13B are sections showing the behavior of theintermediate members transferred to the assembly position by theintermediate member mounting unit;

[0039]FIG. 14 is a side elevation a head fixing unit for curing theadhesive applied to the intermediate members with UV rays;

[0040]FIG. 15 shows a head fixing unit representative of an alternativeembodiment of the present invention;

[0041]FIGS. 16A, 16B and 16C are respectively a front view, a sideelevation and a plan view showing structural elements assembled in anadequate condition by the embodiment of FIG. 15;

[0042]FIGS. 17A and 17B are respectively a front view and a sideelevation showing the structural elements assembled in an inadequatecondition;

[0043]FIG. 18 is a front view showing a first example of the embodimentof FIG. 15;

[0044]FIGS. 19A and 19B are front views showing a second example of theembodiment of FIG. 15:

[0045]FIG. 20 is a front view showing a third example of the embodimentof FIG. 15;

[0046]FIGS. 21A and 21B are front views showing a fourth example of theembodiment of FIG. 15;

[0047]FIG. 22 is a front view showing a fifth example of the embodimentof FIG. 15;

[0048]FIGS. 23A and 23B are respectively a plan view and a sideelevation showing a sixth example of the embodiment of FIG. 25;

[0049]FIGS. 24A and 24B are respectively a plan view and a front viewshowing a seventh example of the embodiment of FIG. 25;

[0050]FIG. 25 is a front view showing an eighth example of theembodiment of FIG. 15;

[0051]FIG. 26 is a front view for describing adhesive applied to asubstantially horizontal second interface particular to the illustrativeembodiment;

[0052]FIG. 27 is a front view for describing the viscosity of adhesiveapplied to a substantially vertical second interface particular to theillustrative embodiment;

[0053]FIG. 28 is a front view of a first interface between a partsupport and an intermediate member included in the illustrativeembodiment;

[0054]FIG. 29 is a front view of the structural elements assembled bythe illustrative embodiment;

[0055]FIG. 30 is a flowchart demonstrating a specific operation of theillustrative embodiment;

[0056]FIGS. 31A and 31B are front views showing a specific procedure forsequentially half-curing adhesive applied to the interfaces;

[0057]FIGS. 32A and 32B are front views showing another specificprocedure for sequentially half-curing the adhesive; and

[0058]FIG. 33 is a front view showing another specific configuration ofthe first interface between the part support and the intermediatemember.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0059] A preferred embodiment of the present invention will be describedhereinafter. The embodiment is implemented as a head unit assemblingapparatus for assembling an ink jet head unit (head unit hereinafter)included in a color ink jet print r by way of example.

[0060]FIG. 1 shows the general construction for the head unit to whichthe illustrative embodiment is applied. As shown, the head unit,generally 1, includes four heads or parts 2. A head support 3 supportsthe heads 2 and, in this sense, plays the role of a part support.Intermediate members 4 are arranged between the head support 3 and theheads 2 and adhered to connect them together. The heads 2 are thereforesupported by the head support 3 via the intermediate members 4.

[0061] As shown in FIGS. 3 and 4, each head 2 includes a nozzle-like inkfeed portion 2 a for feeding ink from an ink cartridge, not shown,mounted to the back of the head 2. The ink fed via the ink feed portion2 a is ejected from a number of nozzle holes 2 b in the form of finedrops toward a paper or similar recording medium. A control board, notshown, is mounted on the back of the head 2 for controlling the electiontiming of the ink drops via the nozzle holes 2 b. A control signal, aswall as other signals, is fed to the control board via a flexible flatcable 2 c. The nozzle holes 2 b of each head 2 are arranged in twoarrays in a head surface 2 d facing the paper, and each array extends inthe direction of paper transport (subscanning direction).

[0062] As shown in FIG. 1, the head support 3 includes substantiallyvertical head support walls 3 a supporting the heads 2 via theintermediate members 4 such that the head surfaces 2 d are exposed fromthe back toward the front. The head support 3 is mounted on a head unitsupport shaft, not shown, and movable back and forth in the direction(main scanning direction) perpendicular to the direction of papertransport. The head unit support shaft is mounted on the body of thecolor printer. Specifically, slide bearings 3 b are slidably mounted onthe above head unit support shaft. A bracket 3 a is positioned at therear of the head support 3 in order to hold ink cartridges respectivelymounted to the ink feed portions 2 a of the heads 2.

[0063] Each head 2 is adhered to the head support walls 3 a via fourintermediate members 4. As shown in FIG. 4, each intermediate member 4is implemented by a generally L-shaped piece having a substantiallyperpendicular first surface 4 a and a substantially horizontal secondsurface 4 b. The first surface 4 a is parallel to the head support wall3 a of the head support 3 while the second surface 4 b is parallel tothe upper surface of a base portion 2 e included in the head 2. Thecontrol board mentioned earlier is built in the base portion 2 e. Theintermediate members 4 are formed of transparent resin transparent forUV rays, so that UV curable adhesive applied to the surfaces 4 a and 4 bcan be cured via the members 4.

[0064]FIG. 2 is a block diagram schematically showing the apparatus forassembling the head unit 1. FIG. 3 shows a specific structure of theapparatus. As shown, the apparatus includes a jig 100, a jig conveyingunit or jig conveying means 200, a jig positioning unit 300 anintermediate member mounting unit 400, a head position adjusting unit500, a nozzle position measuring and head fixing unit 600, and a controland peration unit 700.

[0065] The jig 100 is a loaded with the parts of the head unit 1, i.e.,the heads 2, head support 3, and intermediate members 4 to be assembled.

[0066] As shown in FIG. 3, the illustrative embodiment includes two jigs100 respectively located at setting positions A and B defined on a setstage 201. The jig conveying unit 200 includes a conveying mechanism202. The conveying mechanism 202 conveys the jig 100 back and forthbetween the setting position A or B and an elevating position C definedon the set stage 201 where the jig 100 is movable in the up-and-downdirection. An elevating mechanism 203 moves the jig 100 located at theelevating position C up and down between the set stage 201 and anassembly stage 301 positioned above the set stage 201.

[0067] The jig positioning unit 300 includes a clamping mechanism 302for clamping the jig 100 raised to the assembly stage 301. A positionadjusting mechanism 303 moves the clamping mechanism 302 clamping thejig 100 back and forth between an elevating position D and an assemblingposition E (see FIG. 8) defined on the assembly stage 301, therebyadjusting the stop position of the jig 100 on the stage 301. Measuringmeans 304 measures the position of the jig 100 moved by the positionadjusting mechanism 303.

[0068] The intermediate member mounting unit 400 includes a holdingmechanism 401 for holding the intermediate members 4 set on the jig 100that is located at to the assembling position E. The holding mechanism401 causes the intermediate members 4 to face a preselected adhesiveapplying position. A position adjusting mechanism 402 moves the holdingmechanism 401 holding the intermediate members 4 to a preselectedmounting position between each head 2 and the head support 3 set on thejig 100, thereby adjusting the mounting position of the members 4.Adhesive applying means 403 applies UV curable adhesive to theintermediate members 4 held by the holding mechanism 401. Adhesiveadjusting means 404 adjust the amount of the adhesive to be applied tothe intermediate members 4 by the applying means 403.

[0069] The head position adjusting unit 500 includes head clamping means501 for clamping each head 2 set on the jig 100 having been brought tothe assembling position E. A position adjusting mechanism 502 moves thehead clamping means 501 in the directions parallel to the X axis whichis parallel to the direction of movement of the jig clamping mechanism302, directions parallel to the Y axis and the Z axis perpendicular tothe X axis, and directions of rotations a, and γ having centers ofrotation respectively defined by the X, Y and Z axes, i.e., in sixdifferent directions in total. The position adjusting mechanism 502adjusts the position of the head 2 clamped by the clamping means 501.

[0070] The nozzle position measuring and head fixing unit 600 includes aCCD camera or part position detecting means 601 for detecting the nozzleholes 2 b of each head 2. Measuring means 602 measures the position ofpreselected ones of the nozzle holes 2 b on the bas is of data outputfrom the CCD camera 601. A light source 604 illuminates the nozzle holes2 b to be detected by the camera 601 via a halogen light guide 603. A UVlight source 606 illuminates, via UV light guides 605, the intermediatemembers 4 brought to the preselected mounting position with UV rays.

[0071] The control and operation unit 700 includes a host controller orsequencer and a subcontroller or personal computer. The host controllermainly controls the operation of units driven by air cylinders. Thesubcontroller controls the operation of unite driven by motors andperforms logical and arithmetic operations with image data and measureddata output from the various measuring means.

[0072] Reference will be made to FIGS. 5 and 6 for describing a specificoperation of the illustrative embodiment. A program for executing theoperation to be described is stored in, e.g., a ROM read Only Memory)included in the control and operation unit 700 beforehand and startswhen a main switch, not shown, included in the apparatus is turned on.

[0073] First, the apparatus is initialized (step S1). By theinitialization, the various units of the apparatus each is returned tothe respective home position. For example, the jigs 100 are respectivelybrought to the setting positions A and B or the set stage 201. Theoperator sequentially sets the various parts of the head unit 1 on thejigs 10 located at the positions A and B (step. S2).

[0074] Specifically, each jig 100 is made up of a head support holdingportion, a head supporting portion, and an intermediate membersupporting portion. The head support holding portion colds the headsupport 3 such that the support 3 remains in its orientation forassembly maintains its portions for receiving the heads 2 andintermediate members 4 pen or freely accessible. The head supportingportion supports the heads 2 in such a manner as to guarantee a regionfor adjusting the positions of the heads 2 relative to the head support3 positioned on the head support holding portion. The intermediatemember supporting portion supports the intermediate members 4 in such aposition that the members 4 can be transferred to the head support 3positioned on the head support holding portion.

[0075] As shown in FIGS. 3, 4 and 7, the head support holding portionincludes a stationary stub 102 fixed to a rear a side wall 101 includedin the jig 100. A movable stub 104 is mounted on a front side wall 103also included in the jig 100 and faces the stationary stub 102. Themovable stub 104 is movable toward and away from, the stationary stub102. A push-down member 106 is mounted on a pair of brackets 105respectively fixed to the upper right portions of the inner surfaces ofthe side wells 101 and 103. Three push-up members 107 are positioned onthe bottom well 113 of the jig 100 in order to push up the head support3. The stubs 102 and 104 each has the same outside diameter as the headunit support shaft mentioned earlier. A lug 106 a protrudes fromsubstantially the center of the underside of the push-down member 106.The lug 106 a faces the bracket 3 c of the head support 3 remote fromthe slide bearings 3 b.

[0076] The movable stub 104 extends throughout the side well 103 and isfixed to a bracket 108 positioned outside of the side wall 103. Anotherbracket 109 is mounted on the outer surface of the side wall 103. Thebracket 108 is mounted on a shaft 110 journalled to the bracket 109 andside wall 103 and is slidable in the direction parallel to the axis ofthe movable stub 104. A coil spring 111 is wound round the shaft 110 andconstantly biases the bracket 108 toward the side wall 103. A lever 112to be operated by hand is mounted on the bracket 108 and received in aguide slot 109 a formed in the bracket 109.

[0077] The head support 3 is set on the head support holding portion bythe following procedure. Before setting the head support 3, the operatorpulls the lever 112 toward the operator against the action of the coilspring 111 and locks it in a locking portion included in the guide slot109 a. As a result, the movable stub 104 moves toward the outside of theside wall 103, making the distance between the surfaces of the stubs 104and 102 facing each other greater than the maximum width between theslide bearing 3 b. In this condition, the operator coupled the rearslide bearing 3 b of the head support 3 to the stationary stub 102 andunlocks the lever 112. Consequently, the movable stub 104 mates with thefront slide bearing 3 b of the head support 3 due to the action of thecoil spring 111. Subsequently, the operator sets the three pushupmembers 107 to a preselected height and mounts the push-down member 106to the brackets 105. The lug 106 a of the push-down member 106 pushesthe bracket 3 c of the head support 3 downward.

[0078] By the above procedure, the head support 3 is set at apreselected position on the jig 100. In the head support holdingportion, the stationary stub 102 and movable stub 104 support the slidebearings 3 b of the head support 3 in the same manner as the head unitsupport shaft which allows the heads 2 to move in the main scanningdirection, as stated above. Therefore, by using the stubs 102 and 104 asa reference axis for mounting the heads 2 to the head support 3, it ispossible to extremely accurately position the heads 2 relative to thehead support 3. In addition, the three push-up members 107 positioned onthe bottom well 113 of the jig 100 support the back of the head support3 and thereby insure the horizontal position of the head support 3.

[0079] The head supporting portion is implemented by a head supportmember 115 fixed to the side-walls 101 and 103 at substantially theintermediate between the side walls 101 and 103. The head support member115 is located at a position allowing the heads 2 to be adjusted inposition relative to the head support 3 positioned an the head supportholding portion. As shown in FIGS. 3, 4 and 7, the head support member115 is formed with four surfaces 115 a for positioning the base portions2 e of the four heads 2. Holes. 115 b are formed in the head supportmember 115 such that when the heads 2 are laid on the surfaces 115 a,the ink feed portions 2 a of the heads 2 are respectively received inthe holes 115 b. A cable pocket 115 c is also formed in the head supportmember 115 for accommodating the flexible flat cables 2 c of the heads2. The head support member 115 is configured such that when the heads 2are laid on the surfaces 115 a, the heads 2 each faces the lower portionof the respective head mounting portion between the head support walls 3a of the head support 3 (see FIG. 3).

[0080] The ink feed portion 2 a of each head 2 is received in therespective hole 115 b of the head support member 115, therebypositioning the head 2 on the respective surface 115 a. This eliminatesthe need for special positioning means. When the heads 2 are positionedon the head support member 115, the cables 2 c of the heads 2 areaccommodated in the cable pocket 115 a. Therefore, the clamping means501 which will be described later can clamp the heads 2 without beingobstructed by the cables 2 c.

[0081] The intermediate member supporting portion is implemented by aflat intermediate member support member 116 similar to the head supportmember 115. The intermediate member support member 116 is fixed to theupper left portions of the inner surfaces of the side walls 101 and 103and substantially parallel to the bottom wall 113. As shown in FIGS. 3,4 and 7, two parallel grooves 116 a are formed in the support member 116perpendicularly to the side-walls 101 and 103. Positioning pins 116 bare studded on the bottom of each groove 118 a at equally spacedlocations. Each intermediate member 4 is positioned on the supportmember 116 with its first surface 4 a and second surface 4 brespectively contacting any one of the pins 116 b and the bottom ofeither one of the grooves 116 a.

[0082] The distance between the grooves 116 a, the width of each grooveand the distance between the positioning pins 116 b are selected suchthat when the intermediate members 4 are set on the intermediate membersupport member 116, the members 4 have substantially the samearrangement as when they are mounted to the head support 3 and heads 2.This successfully simplifies the adjustment of the positions of theintermediate members 4 to be effected by the holding mechanism 401 andposition adjusting mechanism 402 which will be described later, andtherefore the configurations and control of the mechanism 401 and 402.

[0083] As shown in FIGS. 4 and 7, the jig 100 includes two stays 114 inaddition to the bottom wall 113 and has an open top. Therefore, theparts of the head unit 1 can be set on the jig 100 from above the jig100. This promotes rapid setting of the parts and rapid removal of thehead unit 1 and enhances the free layout of the nozzle positionmeasuring and fixing unit 800. Further, an opening 113 a is formed inthe bottom wall 113 be low the head support member 115, so that theclamping means 501 which will be described can reach the inside of thehead support 3 from the back side.

[0084] The clamping means 501 is allowed to clamp each head 2 from theback side of the head support 3, as stated above. It follows that thenozzle position measuring and fixing unit 600 can be laid out withgreater freedom above the head support 3, and the hoed unit 1 can bereduced in size and increased in strength. By contrast, if the head 2 ismounted to the head support 3 from above the head support 3, then eachopening 3 d. (see FIG. 4) formed in the head support 3 for receiving thehead 2 must be greater in size than the base portion 2 a of the head 2.This increases the distance between the nearby walls 3 a of the headsupport 3 and therefore the size of the head support 3 while reducingthe strength of the walls 3 a holding the heads 2.

[0085] After the parts of the head unit 1 have been set on the jig 100by the above procedure, a step S3 shown in FIG. 5 is executed. In thestep, S3, whether or not the operator has turned on start switches SW1and SW2 substantially at the same time for causing the conveyance of thejig 100 to start. As shown in FIG. 3, the start switches SW1 and SW2 arepositioned on the set stage 201 in the vicinity of the opposite settingpositions A and B at a suitable distance, so that they will not turn anunless the operator touches them with both hands. This prevents theoperator's hands from being hurt when the jig 100 starts moving.

[0086] The jig conveying mechanism 202 for conveying the jig 100includes two cylinders 204 a and 204 b. When the two start switches SW1and SW2 are turned on substantially at the same time, the cylinder 204a, for example, assigned to the setting position A is turned on (stepS4).

[0087] The cylinders 204 a and 204 b each is implemented by an aircylinder and mounted on a cylinder guide shaft 205 (see FIGS. 3 and 7)in such a manner as to be movable back and forth. The cylinder guideshaft 205 is supported by a pair of brackets 206 mounted on oppositesides of the set stage 201 and extends in parallel to the set stage 201.Bases 207 a and 207 b are respectively loaded with the jigs 100 andposition them at the setting positions A and B. The cylinders 204 a and204 b are respectively fixed to the lower portions of the bases 207 aand 207 b via cylinder brackets 208.

[0088] The bases 207 a and 207 b carry the jigs 100 identical inconfiguration with each other. The following description willconcentrate on the base 207 a located at the setting position A, i.e.,the left position in FIG. 3 by way of example.

[0089] As shown in FIGS. 3 and 7, the jig elevating mechanism 203 whichwill be described includes a table 209 for elevating the jig 100. Thefour sides of the bottom well 113 of the jig 100 can be positioned atsubstantially the center of the upper surface of the base 207 a. Anopening 207 c great enough to receive the table 209 in formed insubstantially the center of the base 207 a. A plate 210 formed ofacrylic resin is fitted on the base 207 a around the opening 207 a, sothat the jig 100 will be positioned slightly above the upper surface ofthe base 207 a.

[0090] Five crank-like jig positioning members 211 are fixed to theupper surface of the base 207 a at the front, rear and left of the plate 210, as viewed in FIG. 7, such that the members 211 respectivelycontact three sides of the bottom plate 113. A pair of guide rails 212are provided on the set stage 201. Rail guides 212 are provided at fourcorners of the underside of the table 207 a and respectively slidablyengaged with the guide rails 212. The guide rails 212 are parallel tothe cylinder guide shaft 205. A presser 214 is positioned at theright-hand side of the base 207 a in order to stop the jig 100 againstinertia when the base 207 a is brought to a stop.

[0091] When the cylinder 204 a is turned on (step S4), the jig conveyingmechanism 202 moves the base 207 a from the setting position A, FIG. 3,to the elevating position C. When the bracket 208 of the cylinder 204 aabuts against a stop 215 located at substantially the center of the setstage 201, the cylinder 204 a stops moving. The position where thecylinder 204 a stops moving is selected such that when the cylinder 204a stops, the table 209 of the jig elevating mechanism 203 facessubstantially the center of the opening 207 c of the base 207 a.

[0092] When the jig 100 is brought to a stop at the elevating positionC, i.e., at substantially the center of the set stage 201, the presser214 driven by an air cylinder, not shown, stops pressing the jig 100.Then, a cylinder 216 for moving the table 209 up and down is turned on(step S5) in order to elevate the table 209. The cylinder 218 alsoimplemented by an air cylinder is constructed to raise or lower astabile support 209 supporting the table 209 when turned on or turnedoff. As shown in FIGS. 3 and 7, the cylinder 216 it mounted on a supportplate 218 which is mounted on the underside of the set stage 201 via acylinder stay 218.

[0093] A positioning pin 220, is studded on the upper surface of thetable 209 while a hole 221 for receiving the pin 220 is formed in thebottom wall 113 of the jig 100. When the cylinder 216 is turned an toraise the table 209, the positioning pin 220 enters the hole 221 withthe result that the jig 100 is positioned on the table 209. As the table209 is further raised, the jig 100 set on the base 207 a and brought tothe elevating position C is transferred to the table 209. As a result,as shown in FIG. 3, the jig 100 is raised by the table 209 to theelevating position C of the assembly stage 301 positioned above the setstage 201.

[0094] As shown in FIGS. 3 and 8, a relatively large elongate opening301 a is formed in substantially the center of the assembly stage 301.The opening 301 a has a width allowing the jig 100 to pass therethroughand a length spanning the distance between the elevating position D andthe assembling position E. A pair of guide rails 305 extend on the uppersurface of the assembly stage 301 at both sides of and in the lengthwisedirection of the opening 301 a. The guide rails 305 extendperpendicularly to the direction in which the jig 100 is moved on theset stage 201, thereby guiding the jig positioning unit 300.

[0095] Rail guides 307 are mounted on four corners of the underside of abase 306 on which the clamping mechanism 302 is counted. The rail guides307 are engaged with the guide rails 305, so that the base 306 ismovable back and forth along the guide rails 305. The base 306 has achannel-like configuration surrounding the path along which the jig 100is elevatable. The clamping mechanism 302 includes a stationary clampmember 308 and a movable clamp member 308 respectively positioned at therear and the front of the base 306.

[0096] Two clamp pins 310 are studded on the stationary clamp member 308and respectively mate with holes 118 a (see FIG. 7) formed in a member118 to be clamped and mounted on the rear side wall 101 of the jig 100.A single clamp pin 311 is studded on the movable clamp member 309 andmates with a single hole 119 a formed in a member 119 to be clamped andmounted on the front side wall 103. A cylinder 312 implemented by an aircylinder drives the movable clamp member 309 toward and away from thestationary lamp member 308. The movable clamp member 309 is usuallyretracted to the front side of the base 306 such that the clamp pin 311does not protrude into the elevation path of the jig 100. An opening 306a is formed in the base 306 in such a position that when the movableclamp member 309 is retracted, the clamp pins 310 of the stationaryclamp member 308 and the clamp pin 311 of the movable clamp member 309each is positioned outside of the elevation path of the jig 100.

[0097] When the cylinder 216 is turned on (step S5, FIG. 5), the table209 raiser the jig 100 to the elevating position D on the assembly stage301, i.e., the position where the clamp pins 310 and 311 respectivelyface the members 118 and 119 a. When the jig 100 is brought to a stop atthe position D, the cylinder 312 is turned on (step S6).

[0098] When the cylinder 312 is turned on, it moves the movable clampmember 309 toward the stationary clamp member 308. As a result, theclamp pins 310 and 311 of the clamp members 309 and 306 respectivelymate with the holes 118 a and 119 a of the jig 100, so that the jig 100is clamped by the base 306. Subsequently, a motor 313 included in theposition adjusting mechanism 303 is turned on for moving the base 306back and forth along the guide rails 305 (step S7).

[0099] As shown in FIG. 8, the motor 313 is a reversible motor fordriving a ball screw 314 via a speed reduction gear not shown. A ballnut 315 including a steel ball is held in threaded engagement with theball screw 314. The ball nut 315 is fixed to the base 306 via achannel-shaped bracket 316. As shown in FIGS. 3 and 8, the motor 313 ismounted on screen-like support members 317 mounted an the right portionof the assembly stage 301 at the front side and rear side, respectively(only the rear support member is shown). A support plate 318 is fixedbetween the upper surfaces of the support members 317. The bell screw314 is journalled to bearings 31 respectively fixed to the front endend-rear end of the support plate 318.

[0100] When the motor 313 causes the ball screw 314 to rotate in theforward direction (step S7), the base 306 moves along the guide rails305 to the rear of the egaembly stage 301. As a result, the jig 100clamped by the base 306 is moved from the position D to the position Eon the assembly stage 301. A linear scale 320 is fixed to the base 306while a scale measuring portion 321 is fixed to the assembly stage 301.The scale measuring portion 321 measures the displacement of the linearscale 320 while sending the result of measurement to the control andoperation unit 700. In response, the control and operation unit 700selectively turns on or turns off the motor 313 and thereby controls thedisplacement of the base 306 with utmost accurately.

[0101] Whether or not the base 306 has reached the assembling position Eis determined (step S8), if the answer of the step S8 is positive (Y),the motor 313 is turned off (step S9). As a result, the jig 100 carriedon the base 306 is accurately brought to a stop at the position E. Whenthe heads 2, head support 3 and intermediate members 4 set on the jig100 each faces a particular assembly start position, a motor ZM includedin the position adjusting mechanism 502 and assigned t the Z axis isturned on (step S10).

[0102] As shown in FIG. 9, the rotor ZM causes a Z axis base 510 to moveup and down along the Z axis perpendicular to the base 308. The motor ZMis fixed to a Y axis table 511. A motor YM assigned to the Y axis causesthe Y axis table 511 to move in the X axis direction parallel to thedirection of movement of the base 306 and the Y axis directionperpendicular to the Z axis direction. The motor YM is fixed to an Xaxis base 512 driven by a motor XM in the X axis direction.

[0103] The motor XM is fixed to a Z axis rotation base 513. A motor ZRMcauses the table 513 to rotate in the r direction about the Z axis. Amotor XRM is mounted on the Z axis base 510 for causing an X axisrotation base 514 to rotate in the a direction about the X axis.Further, a motor YRM is mounted on the X axis base 514 and causes a Yaxis rotation base 515 to rotate in the β direction about the Y axle.

[0104] An arm support 503 and two cylinders 504 and 505 playing the roleof the clamping means 501 are mounted on the Y axis rotation table 514.The cylinders 504 and 505 are implemented by air cylinders. As shown inFIG. 9, arms 507 and 508 stand upright on the tops of the cylinders 504and 505, respectively. The air cylinders 504 and 505 respectively movethe arms 507 and 508 back and forth in the Y axis directionperpendicular to the direction of movement of the base 306. An arm 506extends upward from the arm support 503 and faces the arms 507 and 508.

[0105] When the motor ZM assigned to the Z axis is turned on (step S10),it raises the Z axis base 510. Whether or not the arms 506, 507 and 508of the clamping mans 501 have risen to a preselected clumping positionis determined (step S11). If the answer of the step S11 is Y, the motorZM is turned off in order to stop the elevation of the table 510 (stepS12). As shown in FIGS. 9 and 10A, at the above clamping position, clamppins 506 a, 507 a and 508 a studded on the arms 506, 507 and 508 face toface, respectively, face holes 2 f formed in opposite ends of the base 2c of the head 2 supported by the head support member 115.

[0106] After the Z motor ZM has been turned off, the motor YM assignedto the Y axis is turned on (step S13). As shown in FIG. 10A, the motorYM moves the arm 506 toward the base portion 2 e of the head 2. As shownin FIG. 10B, clamp pin 506 a of the arm 506 mates with the hole 2 f ofthe base portion 2 c (step S14). Then, the motor YM in turned off (stopS15). Subsequently, the cylinders 504 and 505 are turned on (step S16).As shown in FIG. 10B, the cylinders 504 and 505 respectively move thearms 507 and 508 toward the base portion 2 e. Consequently, as shown inFIG. 10G, the clamp pins 507 a and 508 a of the arms 507 and 508 matewith the other holes 2 f of the head base 2 e.

[0107] After the clamp pins 507 a and 508 b have clamped the baseportion 2 e of the head 2 in cooperation with the clamp pin 506 a, themotor ZM assigned to the axis Z is again turned on (% prep S17). At thistime, the motor ZM raises the Z axis base 510 and therefore the arms506-508 to a preselected head mounting position (see FIG. 3). When thearms 506-508 reach the head mounting position, as determined in a stepS18, the motor ZM is turned off in order to stop the elevation of the Zaxis base 510 (step S19).

[0108] Thereafter, the nozzle position measuring means 602 is turned on(step S20, FIG. 6). The measuring means 602 measures the positions ofpreselected ones of the nozzle holes 2 b of the head 2 in the X, Y and Zaxe directions. This is successful to determine whether or not the headsurface 2 d raised by the clamping means 501 is accurately located atthe assembly position relative to the head support 3 positioned on thejig 100.

[0109] Conventional nozzle position measuring means picks up a singlenozzle hole 2 b formed in the surface 2 d with a CCD camera including asolid imaging device. An operating section calculates the position ofthe center of gravity of the resulting image and thereby determines thepositions of the head 2 in the X and Y axis directions. Further, theposition of the head 2 in the Z axis direction is determined on thebasis of defocus data output from an autofocus device built in thecamera.

[0110] The above conventional scheme is disadvantageous for thefollowing reasons. When the camera is focused on a single nozzle hole 2b in order to position the head 2, the positions of the single nozzlehole 2 b in the X, Y and X axis directions can be accurately positioned.However, it is impracticable to accurately measure, based n thepositions of the above nozzle hole 2 b, the positional deviation of theother nozzle holes 2 ascribable to the irregularity and rotation of thesurface 2 d.

[0111] With the conventional scheme therefore, it is extremely difficultto correct the positional deviation of the other nozzle holes 2 bascribable to the above causes. That is, a long period of time andcomplicated calculations are necessary for the head 2 to be positioned.

[0112] In the illustrative embodiment, the head 2 is held by theclamping means 501 and position adjusting mechanism 502 in such a manneras to be adjustable in position relative to the head support 3. In thiscondition, the position of the head 2 is varied in order to detect threepreselected points of the head 2 by using CCD cameras, so that the head2 can be adjusted relative to the heed support 3. In the illustrativeembodiment, at least three CCD cameras assigned to the above threepoints have their optical axes inclined relative to the surface of thehead 2 to be detected, i.e., the head surface 2 d.

[0113] Specifically, as shown in FIGS. 3 and 11, the measuring means 602of the illustrative embodiment includes CCD cameras 601 a-601 e. Thecamera 601 a detects the position of, e.g., the leftmost nozzle hole 2b-1 of the front array, as viewed in FIG. 11, in the inclined direction.The camera 601 b detects the position of the nozzle hole 2 b-1 in thevertical direction. A halogen light guide 603 a guides halogen lightoutput from the light source 504 to the nozzle hole 2 b-1. The camera601 c detects the position of the rightmost nozzle hole 2 b-2 of thefront array, as viewed in FIG. 11, in the inclined direction. The camera601 d detects the position of the nozzle hole 2 b-2 in the verticaldirection. A halogen light guide 603 b guides the halogen light to thenozzle hole 2 b-2. The camera 601 e detects the position of the centernozzle hole 2 b-3 of the rear array, as viewed in FIG. 11, in theinclined direction. A halogen light guide 603 b guides the halogen lightto the nozzle hole 2 b-3 via a mirror 606 c.

[0114] As shown in FIG. 3, a top plate 331 is connected to the assemblystage 301 by a plurality of posts 330. A support plate 610 is mounted onthe top plate 331 and extends downward through an opening 331 a formedin substantially the center of the top plate 331. The measuring means602 is mounted on the support plate 610.

[0115] With the three CCD cameras 601-a through 601 c, it is possible todetect the nozzles 2 b-1 through 2 b-3 or three preselected points ofthe-head surface 2 d and determine their positions on the X, Y and Zcoordinates. It is therefore not necessary to use the autofocus devicecustomarily assigned to the Z axis direction.

[0116] In the illustrative embodiment, the measuring means 602 detectsthe nozzle holes 2 b formed in the surface, 2 d of the head. As for thesurface of a part lacking such portions to be detected, e.g., a solidimaging device, marks to be detected may be provided on the surfacebeforehand.

[0117] Assume that at least three CCD cameras have their optical axespositioned vertically to the head surface 2 d for detecting the abovethree points. Then, because the optical axes of the camera are parallelto each other, the distance between the optical axes is unconditionallydetermined by the outside diameter of the cameras. Therefore, when theheed 2 is relatively small and has the maximum distance between itsthree points smaller than the minimum distance between the optical axisof the cameras, the optical axes are positioned outside of the threepoints of the head 2. In this condition, the cameras cannot detect thethree points of the head 2.

[0118] By contrast, in the illustrative embodiment, the optical axes ofat least three CCD cameras 601 a through 601 c are inclined relative tothe surface 2 of the head 2 and can therefore be oriented in desireddirections. This successfully prevents the minimum distance betweenthree points that can be detected from being unconditionally determinedby the outside diameter of the cameras. That is, it is possible todetect desired three points of the head 2 and accurately position thehead 2 without regard to the size of the head 2.

[0119] Image date representative of the nozzle holes 2 b-through 2 b-3and output from the cameras 601 a through 601 e are monitored on the CRT(Cathode Ray Tube) of the subcontroller or personal computer via thecontrol and operation unit 700. Assume that the positions and, shapes ofthe images being monitored are different from positions and shapes setbeforehand. Then, it Is determined that the head surface 2 d does notaccurately face the head mounting position (step S21, FIG. 6). As aresult, the position adjusting mechanism 502, FIG. 9, is turned on (stepS22). Specifically, the motors of the mechanism 502 are driven to shiftthe head 2 in the six directions X, Y, Z, α, β and γ. When the surface 2d accurately faces the head mounting position (Y, step S21) themeasuring means 602 and adjusting mechanism 502 are turned off (stepS23).

[0120] The head 2 is positioned at the head mounting position relativeto the head support 3 by the above procedure. Subsequently, the positionadjusting mechanism 402 included in the intermediate member mountingunit 400 is turned on (step S24) in order to drive the holding mechanism401. As shown in FIGS. 3 and 12, the holding mechanism 401 includes twoair chucks 405 and 406 capable of simultaneously chucking fourintermediate members 4 necessary for adhering a single head 2 to thehead support 3.

[0121] As shown in FIG. 3, the air chucks 405 and 406 are fixed to theend portion of a chuck arm 407. When the air chucks 405 and 406 are heldin a home position, they are positioned right above the two grooves 116a, FIG. 4, of the intermediate member support member 116 set on the jig100. As shown in FIG. 12, the air chucks 405 and 406 each has arectangular lower end or chucking portion. With this configuration, eachof the air chucks 405 and 406 can hold two intermediate members 4located between two positioning pins 110 b studded in the associatedgroove 116 a, while maintaining the members 4 substantially in their setpositions. Passageways 405 a and 408 a are respectively formed in theair chucks 405 and 400 in order to selectively suck or blow air via thebottoms and opposite sides of their chucking portions.

[0122] A shaft 407 a is fixed to the base end of the chuck arm 407 andextends along the Y axis. The shaft 407 a is supported by a chuckbracket 408 in such a manner as to be rotatable by substantially 180degrees. A cylinder 409 implemented as an air cylinder supports thecheck bracket 408 such that the bracket 408 is movable up and down alongthe Z axis. As shown in FIG. 3, a robot 411 is mounted on a plate 410fixed to the rear side of the assembly stage 301. The robot 411 movesthe above cylinder 409 back and forth along the Y axis. A cylinder 412also implemented by an air cylinder is fixed to the chuck bracket 408and causes the shaft 407 a to rotate.

[0123] When the position adjusting mechanism 402 is turned on (stepS24), the cylinder 409 lowers the chuck bracket 408 along the Z axis. Asa result, the chucking portions of the air chucks 405 and 406 arelowered to a position where each of them can chuck two of theintermediate members 4 set on the support member 116, as indicated by anarrow a in FIG. 12. The lowered position of the air chucks 405 and 406is determined by a lower stop 409 a fixed to the lower portion of thecylinder 409; a positioning piece 408 a provided an the bracket 408abuts against the lower stop 409 a.

[0124] Subsequently, air is sucked via the passageways 405 a and 408 a,producing vacuum around the chucking portions of the air chucks 405 and406. As a result, the air chucks 405 and 408 retain two intermediatememberes 4 each.

[0125] After the air chucks 405 and 406 have chucked the intermediatemembers 4, the cylinder 409 operates in the reverse direction in orderto lift the chuck bracket 408 to a preselected level. Then, the cylinder412 causes the shaft 407 a to rotate by substantially 180 degrees, asindicated by an arrow b in FIG. 12. The cylinder 409 operating in thereverse direction lifts the chuck bracket 408 until the positioningpiece 408 a of the bracket 408 abuts against an upper stop 409 b fixedto the upper portion of the cylinder 409, as indicated by an arrow c inFIG. 12. Consequently, the intermediate members 4 retained by the airchucks 405 and 406 are turned upside down and cause their surfaces 4 aand 4 b to fare the tops and both sides of the chucking portions of theair chucks 405 and 406.

[0126] The adhesive applying means 403 includes a pair of syringes 431positioned above the air chuck 405 and each having a pair of nozzles 430for applying the UV curable adhesive to the surfaces 4 a and 4 b of eachintermediate member 4. A heater 432 playing the role of the adhesiveadjusting means 404 surrounds the respective syringe 431. The heaters432 each maintains the UV adhesive at a preselected temperature (about30° C.) providing the adhesive with optimal viscosity.

[0127] As shown in FIG. 3, each syringe 431 is fixed to a bracket 436via a syringe holder 435. The bracket 436 is supported by a bracketholder 437 mounted on the underside of the top plate 331 and is slidablein the Y axis direction. The operator can therefore pull out thesyringes 431 to the left of the device body, FIG. 3, by holding a lever438 fixed to the bracket 406. This facilitates the replenishment of theUV curable adhesive to each syringe 431 and prevents the operator fromtouching the heater 432.

[0128] After the intermediate members 4 retained by the air chucks 405and 406 have been turned upside down, as stated above, the nozzles 430of the syringes 431 are caused to face the surfaces 4 a and 4 b of thetwo intermediate members 4 hold by the air chuck 405, as shown in FIG.12.

[0129] Subsequently, the adhesive applying means 403 is turned on (stepS25. Specifically, the UV curable adhesive is applied to the surfaces 48and 4 b of the two intermediate members 4 held by the air chuck 405 viathe two nozzles 430 of the two syringes 431. After the application ofthe adhesive to the surfaces 4 a and 4 b of the above two intermediatemembers 4, the robot 411 shifts the other air chuck 406 positioned atthe left, as viewed in FIG. 3, rightward to the position where the airchuck 405 has been positioned. As a result, the surfaces 48 and 4 b ofthe two intermediate members retained on the top and both sides of theholding portion of the air chuck 406 by suction face the two nozzles 430of the two syringes 431. Then, the adhesive applying means 403 is againturned on in order to apply the adhesive to the surfaces 4 a and 4 b viathe nozzles 430 of the syringes 431.

[0130] After the application of the adhesive to the four intermediatemembers 4 held by the air chucks 405 and 406, the air chucks 405 and 406are returned to the previously mentioned home positions. At the sametime, the robot 411 moves the air chucks 405 and 406 to preselectedpositions above the assembling position between the head 2 held at themounting position and the head support 3. Subsequently, the cylinder 409is turned on to lower the air chucks 405 and 406. Consequently, as shownin FIG. 13A, the four intermediate members 4 held by the air chucks 405and 406 face the mounting position between the head 2 and the headsupport 3.

[0131] In the above condition, air is jetted via the passageways 405 aand 406 a of the air chucks 405 and 406. As a result, the surfaces 4 aand 4 b of the four intermediate members 4 are released from the airchucks 405 and 406 and brought into close contact with the expectedportions of the head 2 and head support 3. Thereafter, the air chucks405 and 406 are returned to their home positions, and then the positionadjusting mechanism 402 is turned off (step S26).

[0132] After the step S26, the head fixing unit 600 is turned on (stepS27). Specifically, as shown in FIG. 14, the two UV light guides 605retracted from the Y axis passage assigned to the air chucks 405 and 406are moved to a position above the head 2 by a cylinder or air cylinder620. In this condition, the UV light source 606 is turned on to issue UVrays toward the adhesive present on the surfaces 4 a and 4 b of theintermediate members 4 via the intermediate members 4. The adhesive iscured by the UV rays and fix the head 2 and head support 3 to each othervia the intermediate members 4.

[0133] An air tube 621 is positioned above each of the light guide 605and joined with the light guide 605 by a respective tie member 622. Air,preferably cool air, is blown out of such air tubes 621 toward theintermediate members 4 at the time of emission of the UV rays. This airprotects the intermediate members 4 from thermal deformation ascribableto the UV rays and obviates the displacement of the head 2 and headsupport 3 ascribable to thermal stress.

[0134] After the head 2 has been fixed to the head support 3 by theabove procedure, whether or not another head 2 should be fixed to thehead support 3 is determined (step S28). Assume that the apparatus is soprogrammed as to sequentially fix the other heads 2 to the head support3. Then, a head assembly routine for executing the above sequence ofassembling steps is repeatedly executed until all the predeterminednumber of heads 2 have been fixed to the head support 3 (step S29). Atthis time, the data derived from the position adjustment of thepreceding head 2 relative to the head support 3 are referenced asposition adjustment data when the following head 2 is fixed to the headsupport 3. When all the preselected number of heads 2 are fully fixed tothe head support 3 (N, step S28) the various units start returning totheir home positions (step S30).

[0135] At the beginning of the step S30, the measuring means 602 isagain turned on (step S31) to measure the positions of the threeparticular nozzle holes of each head 2. The result of this measurementshows whether or not the heads 2 are dislocated during assembly.Specifically, the control and operation unit 700 compares the dataoutput from the measuring means 602 before find after the assembly andsends the result of decision on the configuration of the heads 2 to theCRT (step S32). The program ends when the various unit: are returned totheir home positions (Y, step S33).

[0136] The illustrative embodiment has two setting positions A and B onthe set stage 201, as stated with reference to FIG. 3. The paths betweenthe setting positions A and B and the assembling position E along whichthe conveying unit 200 conveys the jig 100 can be switched by thecontrol and computation unit 700. Therefore, it is possible to conveyone jig 100 conveyed from one setting position A to the assemblingposition E and completed assembly at the position E to the other settingposition B. It is also possible to feed one jig 100 from one settingposition A to the assembly position E end set, while the above jig 100has its parts assembled, the structural parts of another head unit onthe other jig 100 located at the other setting position B. Theillustrative embodiment therefore reduces the operator's waiting time atthe time of satting of the structural parts on the jig 100 end therebyenhances efficient assembly.

[0137] Curing the adhesive with UV rays via the intermediate member 4,as stated earlier, brings about the following problems, as determined bya series of experiments. The UV rays cause the composition of thetransparent intermediate members 4 to change and cause the members 4 tocolor in muddy yellow little by little. Because the UV transmission ofsuch colored intermediate members 4 decreases, the UV rays cannot fullycure the adhesive unless radiated for more than the expected period oftime via the intermediate members. The decrease in the curing efficiencyof the adhesive and therefore the extended radiation of the UV raysheats the intermediate members 4 to such a degree that the members 4deform.

[0138] In order to solve the above problem, as shown in FIG. 15, theillustrative embodiment additionally includes a bandpass filter 630positioned on the optical path of each UV light guide 605, The bandpassfilter 630 cuts UV rays lying in the wavelength range which would causethe property of the intermediate members 4 to change. It wasexperimentally found that the bandpass filter 630 successfully preventedthe intermediate members 4 from coloring when cutting UV rays lying in ashort wavelength range below about 300 nm. Preferably, the bandpassfilter 630 should also cut UV rays lying in a long wavelength rangeheating the intermediate members 4 to an excessive degree.

[0139] Further, as shown in FIG. 5, the bandpass filter 630 it notlocated at the light source side where the UV rays generate a greatamount of heat, but located on the output optical path cf the UV lightguide 605 and held by a filter mount 631. This reduces the thermalstress of the filter 630 itself during the radiation of the UV raystoward the adhesive.

[0140] During UV radiation, air is sent from the air tube 621 to theintermediate member 4 in order to cool off the member 4. This preventsthe intermediate member 4 from being excessively heated during UVradiation and thereby obviates the fall of assembling accuracyascribable to the thermal deformation of the member 4.

[0141] In the above embodiment, the adhesive is applied to the first endsecond surfaces (interfaces hereinafter) 4 a and 4 b of eachintermediate member 4 intervening between the head 2 and the headsupport 3. In this case, the adhesive is not always applied to each ofthe interfaces 4 and 4 b to a preselected thickness over a preselectedarea although it may be fed in a preselected amount. Specifically,adhesive used to mount the head 2 or similar part usually has relativelyhigh viscosity so as not to drop and is apt to protrude in the form ofyolk when applied to the a surface of the part due to the surfacetension of the adhesive.

[0142] Assume that the structural members are assembled by the adhesiveprotruding from the surfaces of the members, as stated above. Then, itis likely that the area of the adhesive on each structural member issmaller than the expected adhering surface and causes the members tocome off due to short adhesion strength. In addition, when the thicknessof the adhesive differs from the first interface 4 a to the secondinterface 4 b, the structural members are displaced from each other whenassembled. Moreover, the protuberance of the adhesive just afterapplication is not constant, rendering the stress inside of the adhesiveirregular during curing. Therefore, should the structural members beassembled without any processing following the application of theadhesive, the head 2 would be inclined relative to the head support 3.In addition, it needs a long period of time for the adhesive protrudingfrom the adhering surfaces to be cured, resulting in low productivity.

[0143] An alternative embodiment of the present invention will bedescribed hereinafter which is capable of obviating short adhesionstrength and positional deviation of the head 2 or similar part, headsupport 3 or similar part support, and intermediate members 4, andenhancing productivity during assembly. Let the head 2 and head support3 be referred to as a part 2 and a part support 3, respectively.

[0144] FIGS. 16A-16C show a condition wherein the part 2, part support 3and intermediate member 4 are assembled in a preselected position freefrom positional errors. As shown, in the accurate condition, curedadhesive P has a preselected thickness t1 between the part 2 and theintermediate member 4 and has a preselected thickness t2 between thepart support 3 and the intermediate member 4. Also, the adhesive Poccupies a preselected area of L1×L2 between the part 2 and theintermediate member 4 and occupies a preselected area of L3×L4 betweenthe part support 3 and the intermediate member 4. FIGS. 17A and 17B showa specific condition wherein the part 2 and part support 3 and theintermediate member 4 assembled together are dislocated relative to eachother. As shown, the adhesive fails to have the above correct dimensionst1, t2, L1×L2 and L3×L4.

[0145] Briefly, in the illustrative embodiment, pressing means pressesthe intermediate member 4 against the part 2 and part support 3 so as tospread the adhesive P applied to the first and second interfaces 4 a and4 b of the intermediate member 4. This successfully allows the part 2and part support 3 and the intermediate member 4 to be accuratelyassembled in a preselected position free from positional deviation. Thatis, the pressing member increases the area which the adhesive P occupieson each of the interfaces 4 a and 4 b and thereby increases the adhesionstrength. In addition, the pressing member substantially uniforms thethickness and configuration of the adhesive P.

[0146] Specific examples of this embodiment are as follows.

EXAMPLE 1

[0147] As shown in FIG. 16, the pressing means for pressing theintermediate member 4 against the part 2 and part support 3 isimplemented byes single pin 10. The pin 10 is movable toward and awayfrom the intermediate member 4 at such an angle that it exertssubstantially the same components of a force on the first and secondinterfaces 4 a and 4 b. As a result, the adhesive P applied to theinterfaces 4 a and 4 b is spread between the part 2 and part support 3and the intermediate member 4, as illustrated. Consequently, the area ofthe adhesive on each of the interfaces 4 a and 4 b increases, increasingthe adhesion strength between the associated structural elements. Inaddition, the thickness and configuration of the adhesive P aresubstantially uniformed.

EXAMPLE 2

[0148] As shown in FIGS. 19A and 19B, the pressing means is implementedby a first pin 11 and a second pin 12 movable toward and away from theintermediate member 4. The two pins 11 and 12 are respectively movablein the direction substantially perpendicular to the second interface 4 band the direction substantially perpendicular to the first interface 4a. That is, the pins 11 and 12 press the substantially vertical surfaceand substantially horizontal surface of the intermediate member 4independently of each other. As a result, the adhesive P present on theinterface 4 a and the adhesive P present on the interface 4 b can bespread independently of each other. It follows that even when the amountor the kind of the adhesive to be applied to one interface is changed,the structural elements can be evenly assembled without any positionaldeviation after the curing of the adhesive P.

EXAMPLE 3

[0149] As shown in FIG. 20, the pressing means is implemented by asingle air nozzle 13. The air nozzle 13 blows air toward theintermediate member 4 at such an angle that it exerts substantially thesame components of a force derived from air on the first and secondinterfaces 4 a and 4 b. Air sent from the air nozzle 13 presses theintermediate member 4 against the part 2 and part support 3 and therebyspreads the adhesive applied to the two interfaces 4 a and 4 b.Consequently, the area of the adhesive P on each of the interfaces 4 aand 4 b increases, increasing the adhesion strength between theassociated structural elements. In addition, the thickness andconfiguration of the adhesive P are substantially uniformed.

[0150] Further, air pressing the intermediate member 4 simplifiesarrangements around the position for adjusting the position of theindividual structural element, compared to the mechanical pressingmeans. This facilitates the layout of the various holding means endposition detecting means and frees the intermediate member 4 from marksascribable to the mechanical pressing means.

EXAMPLE 4

[0151] As shown in FIGS. 21A and 21B, the pressing means is implementedby a first air nozzle 14 and a second air nozzle 15. The air nozzles 14and 15 blow air toward the intermediate member 4 in the directionsubstantially perpendicular to the second interface 4 b and thedirection substantially perpendicular to the first interface 4 a,respectively. The air nozzles 14 and 15 are capable of pressing the twosurfaces 4 b and 4 a independently of each other and therefore spreadingthe adhesive P independently of each other without damaging theintermediate member 4. It follows that even when the amount or the kindof the adhesive to be applied to one surface is changed, the structuralelements can be evenly assembled without any positional deviation afterthe curing of the adhesive P.

EXAMPLE 5

[0152] As shown in FIG. 22, the pressing means is implemented by asingle air nozzle 16 formed with a first and a second air ejection port16 a and 16 b, respectively. The air ejection ports 16 a and 16 b ejectair in the direction substantially perpendicular to the first interface4 a and the direction substantially perpendicular to the secondinterface 4 b. The air nozzle 16 blows air substantially evenly via thetwo ports 16 a and 16 b without resorting to delicate air adjustment, sothat the two interfaces 4 a and 4 b can be pressed by the same force.This allows the adhesive P to be spread on both interfaces 4 a and 4 bunder substantially the same condition. It follows that the sameadhesion strength is achievable between the part 2 and the intermediatemember 4 and between the part support 3 and the intermediate member 4.Therefore, even when a load acts on the part 2, the part 2 and adhesiveP are prevented from being separated due to the concentration of astress. If desired, an electromagnetic valve may be used to vary theamount and therefore the force of air to be sent from each of the port16 a and 16 b.

EXAMPLE 6

[0153]FIG. 23A shows a plurality of (two in this example) first pins 17a and 17 b while FIG. 24B shows a plurality of (two in this example)second pins 18 a and 18 b. The first pins 17 a and 17 b are second pins18 a and 18 b constitute the pressing means for pressing theintermediate member against the part 2 and part support 3, Specifically,the pins 17 a and 17 b are movable back and forth in the directionsubstantially perpendicular to the first interface 4 a of theintermediate member 4. The pins 18 a and 18 b are movable back and forthin the direction substantially perpendicular to the second interface 4 bof the intermediate member 4. In this configuration, the pressures ofthe pins 17 a and 17 b to act on the surface 4 a do not concentrate, butare scattered. This is also true with the pressures of the pins 18 a and18 b to act on the surface 4 a. This prevents the intermediate member 4front tillting and further uniforms the thickness of the adhesive P oneach of the interfaces 4 a and 4 b.

EXAMPLE 7

[0154] As shown in FIGS. 24A and 24B, Example 7 is similar to Example 4(FIGS. 21A and 218) except that air nozzles 14 and 5 have flared nozzleholes 14 a and 15 a, respectively. The flared nozzle holes 14 a and 15 aeject air onto substantially the entire first and second surfaces 4 aand 4 b, respectively. If desired, the flared air nozzle holes 14 a and15 b each may be replaced with a plurality of nozzle holes. In thisconfiguration, air from the air nozzle 14 and air from the air nozzle 15are substantial ly evenly sent to the interfaces 4 a and 4 b,respectively. This prevents the intermediate member 4 from tilting andfurther uniforms the thickness of the adhesive P on each of theinterfaces 4 a and 4 b.

[0155] The adhesive is not always applied to each of the surfaces 4 aand 4 b to a preselected thickness over a preselected area although itmay fade in a preselected amount, as stated earlier. Specifically, theadhesive for adhering the part 2 and intermediate member 4 and the partsupport 3 and intermediate member 4 should preferably spread to acertain degree due to its own weight when app lied to the surfaces 4 aand 4 b and thereby form layers of substantially uniform thickness. Forthis reason, such adhesive should preferably have relatively highfluidity, i.e., relatively low viscosity.

[0156] However, assume that the adhesive having high fluidity, or lowviscosity, is applied to the substantially vertical first interface 4 aand substantially horizontal second interface 4 b in order to connectthe part 2 and part support 3 via the intermediate member 4. Then, suchliquid-like adhesive on the first interface 4 a is apt to drop due toits own weight or to turn round to the second interface 4 b. When theadhesive drops or turns round to any other position, the amount of theadhesive applied to the interface 4 a and that of the adhesive appliedto the interface 4 b differ from the initial amount. As a result, theadhesive layer formed on the interfaces 4 a and 4 b are different inthickness from each other.

[0157] In the above condition, the positional relations between the part2 and the intermediate member 4 and between the part support 3 and theintermediate member 4 are quite likely to differ from the time ofposition adjustment to the time of completion of the assembly. Errors inthis kind of positional relations cannot be corrected by the positionadjustment beforehand because the drop or the turn-round of the adhesiveor an increase or a decrease in the amount of the adhesive ascribablethereto cannot be estimated. By contrast, errors ascribable to thecontraction of the adhesive due to curing can be corrected by theposition adjustment beforehand because the positional deviation of theindividual member is proportional to the amount and area of applicationof the adhesive.

[0158] Another alternative embodiment of the present invention which isa solution to the above problem will be described with reference to FIG.25. As shown, adhesive P1 applied to the first or substantially verticalinterface 4 a has higher viscosity, or lower fluidity, than adhesive P2applied to the second or substantially horizontal interface 4 b. Theadhesive P1 applied to the interface 4 a does drop or turn round toother portions.

[0159] Although the adhesive P2 applied to the interface 4 b hascomparatively high fluidity, or comparatively low viscosity, it does notdrop or turn round to other portions because the interface 4 b issubstantially horizontal. In addition, as shown in FIG. 26, the adhesiveP2 spreads due to its fluidity and can be automatically uniformed inthickness 6.

[0160] As shown in FIG. 27, the adhesive P1 applied to the verticalsurface 4 a should preferably have viscosity causing the adhesive P1 tospread downward due to gravity over an area A2 which is substantiallydouble the area A1 of the adhesive P1 initially applied. This allows theadhesive P1 applied to the surface 4 a to spread within a range notcausing it to drop or turn round.

[0161] Further, as shown in FIG. 28, recesses 3 a and 4 c may berespectively formed in the lower portion of the part support 3 and thelower portion of the vertical surface 4 a to which the adhesive P1 isapplied. When the adhesive P1 applied to the surface 4 a spreadsdownward due to its own weight, it is scattered into the recesses 3 aand 4 c end stopped thereby. As a result, the thickness of the adhesiveP1 decreases to, in turn, increase the surface tension of the adhesiveP1. The adhesive P1 is therefore prevented from spreading more thannecessary, i.e., dropping.

[0162] As shown in FIG. 29, the illustrative embodiment effects, beforethe adjustment of the relative position of the part support a and part2, half-curing of at least the adhesive P1 applied to the substantiallyvertical interface 4 a so as to prevent it from dropping due to its ownweight. The half-cured adhesive P1 does not drop or turn round to otherportions.

[0163] Reference will be made to FIG. 30 for describing a specificprocedure for half-curing both the UV adhesive P1 applied to thesubstantially vertical interface 4 a and the UV adhesive P2 applied tothe substantially horizontal interface 4 b. The procedure begins whenthe step S27, FIG. 6, is executed after the surfaces 4 a and 4 b of theintermediate member 4 have been brought into close contact with the part2 and part support 3 (step S26, FIG. 6).

[0164] As shown in FIG. 30, when the step S27 begins the head fixingunit is turned on. In response, the head fixing unit causes the cylinder620 to move the UV light guides 605 from the retracted position outsideof the Y axis path of the air chucks 405 and 408 to the position abovethe head 2 (step S27 a), as stated earlier with reference to FIG. 14. Inthis condition, the UV light source 606 is turned on to issue UV rays(step S27 b). The UV rays illuminate the adhesive P1 on the interface 4a and the adhesive P2 on the interface 4 b via the UV light guides 605and intermediate members 4 (step S27 b). At this instant, the durationof the UV radiation is selected to be long enough to half-cure at leastthe adhesive P1 on the substantially vertical interface 4 a to a degreepreventing it from dropping due to its own weight (1 second in theillustrative embodiment). By the UV radiation, the adhesive P1 andadhesive P2 are half-cured, temporarily connecting the part 2 and partsupport 3 via the intermediate members 4.

[0165] On the clapse of the above period of time (Y, step S27 c), the UVradiation of the UV light source 606 is interrupted (step S27 d). Inthis condition, the position adjustment mechanism 502 is turned on inorder to adjust the position of the part or head 2 relative to the partsupport 3, (step S27 a). At this instant, the adhesive P1 and adhesiveP2 half-cured on the interfaces 4 a and 4 b, respectively, do not dropor turn round to other portions. In addition, the displacement of thepart 2 relative to the part support 3 is not obstructed at all.

[0166] On the completion of the position adjustment of the part 2 orhead (Y, step 27 f), the position adjusting mechanism 602 is turned off(step S27 g). If the above position adjustment does not complete due tosome error (N, step S27 f), then an error message is displayed on theCRT.

[0167] When the position adjusting mechanism 502 is turned off, the UV,light source 606 is again turned on to radiate UV rays. The UV raysagain illuminates the adhesive on the intermediate members 4 via the UVlight guides 605 and members 4 (step S27 h). At this time, the durationof the UV radiation is selected to be long enough to fully cure theadhesive P1 and P2 (40 seconds in the illustrative embodiment). Theadhesive P1 and P2 now fully cured firmly connect the part 2 and partsupport 3 via the intermediate members 4. On the elapse of the aboveperiod of time (Y, step S27 l), the UV light source 606 is turned off(step S27 j).

[0168] Subsequently, the UV light guides 605 are returned to theirretracted positions (step S27 k). This is followed by the step S28 shownin FIG. 6.

[0169] In the illustrative embodiment the part is adjusted in positionrelative to the part support 3 after the half-curing of the 4 b, asstated above. In this case, if the displacement of the part 2 relativeto the part support 3 is relatively great, then the adhesive existing anthe interface 4 a or 4 b perpendicular to the direction of displacementof the part 2 is apt to come off the part support 3. For example, whenthe part 2 shown in FIG. 29 is noticeably displaced in the directionindicated by an arrow a, the adhesive P1 present on the interface 4 aperpendicular to the direction a is apt to come off the part support 3.

[0170] In light of the above, as shown in FIG. 31A specifically, theillustrative embodiment first half-cures the adhesive P1 applied to thefirst interface 4 a and then adjusts the position of the part 2 in thehorizontal direction (arrow a) relative to the part support 3. At thisstage, the adhesive P2 on the second surface is not cured at all.Therefore, although the displacement of the part 2 relative to the partsupport 3 in the horizontal direction may be great, the half-curedadhesive P1 on the interface 4 a perpendicular to the above directionexerts a greater adhesion force than the non-cured adhesive P2 on theinterface 4 b. This prevents the adhesive P1 from coming off the partsupport 3 despite the above movement of the part 2.

[0171] Assume that the part 2 held in the condition shown in FIG. 31A issimply lowered by the position adjustment. Then, because the adhesionforce of the non-cured adhesive P2 on the interface 4 b is smaller thanthat of the half-cured adhesive P1 on the interface 4 a, the adhesive P2is apt to come off the part 2 due to the above displacement of the part2.

[0172] To solve the above problem, as shown in FIG. 31B, theillustrative embodiment half-cures the adhesive P2 on the interface 4 bto a higher degree than the half-cured adhesive P1 and then moves thepart 2 adjusted in the horizontal direction a in the vertical directionindicated by an arrow b. As a result, the half-cured adhesive on theinterface 4 b perpendicular to the direction of the downward movement ofthe part 2 achieves a greater adhesion force than the half-curedadhesive P1. The adhesive P2 is therefore prevented from coming off thepart 2 despite the vertical movement of the part 2.

[0173]FIGS. 32A and 32B each shows a particular method for half-curingthe adhesive P1 on the interface 4 a and then half-curing the adhesiveP2 on the interface 4 b to a higher degree than the adhesive P1, asstated above. In FIG. 32A, the adhesive P1 on the interface 4 a is ahalf-cured via a first UV light guide 605, and then the adhesive P2 onthe interface 4 b is half-cured via a second UV light guide 605 b to theabove particular degree. In FIG. 32B, the adhesive P1 on the interface 4a is half-cured first. Subsequently, the UV light guide 605 is shiftedto a position for illuminating the adhesive P2 on the interface 6 b, asindicated by a dash-and-dot line, or a mirror 640 is inserted into theoptical path of the light guide 605, as indicated by a dashed line. Thatis, the optical path of the light guide 605 is so switched as toilluminate the adhesive P2. In this condition, the adhesive P2 ishalf-cured to the abov particular degree.

[0174] As shown in FIG. 33, recesses 3 a and 4 c may be respectivelyformed in the lower portion of the part support 3 and the lower portionof the substantially vertical interface 4 a to which the adhesive P1 isapplied. When the adhesive P1 applied to the interface 4 a spreadsdownward due to its own weight, it is scattered into the recesses 3 aand 4 c and stopped thereby. As a result, the thickness of the adhesiveP1 decreases to, in turn, increase the surface tension of the adhesiveP1. The adhesive P1 is therefore prevented from spreading more thannecessary. i.e., dropping.

[0175] In summary, it will be seen that the present invertion provides amethod and an apparatus for assembling parts having varipusunprecedented advantages, as enumerated below.

[0176] (1) A part and a part support are connected together by use ofphotocuring adhesive with the intermediary of intermediate membersformed of a material transparent for light. At the a instant, a bandpassfilter cuts light lying in a wavelength range causing the property ofthe intermediate members to change. The intermediate members aretherefore prevented from coloring or deforming despite the radiation ofthe light. Further, the intermediate members are free from deformationascribable to heat derived from the radiation. At the same time, thestructural parts are free from a decrease in assembling accuracyascribable to the deformation of the intermediate members.

[0177] (2) Pressing means presses the intermediate members against thepart and part support. As a result, adhesive applied to a first and asecond interface is spread between the first interface and the part andbetween the second interface and the part support. Therefore, the areaoccupied by the adhesive on each interface and therefore the adhesionstrength increases. In addition, the thickness and configuration of theadhesive on each interface can be uniformed in order to enhance theaccuracy of toe individual structural part.

[0178] (3) The adhesive applied to the first or substantially verticalinterface has higher viscosity than the adhesive applied to the secondor substantially horizontal interface. The adhesive on the firstinterface is therefore prevented from dropping or turning round to otherportions. It follows that the thickness of the adhesive for connectingthe part and intermediate member and the part support and intermediatemember is uniformed, further enhancing the accurate assembly of the partand part support.

[0179] (4) Before the relative position of the part and part support isadjusted, at least the adhesive applied to the first interface ishalf-cured so as not to drop due to its own weight. This is alsosuccessful to prevent the adhesive from dropping and therefore tofurther enhance the accurate assembly.

[0180] Various modifications will become possible for those skilled inthe art after receiving the teachings of the present disclosure withoutdeparting from the scope thereof.

1. A method of adhering a first member to a second member via anintermediate member, said method comprising the steps of: positioningsaid first member and said second member relative to each other;applying a first adhesive to a first surface destined to comprise afirst interface between said first member and said intermediate member;applying a second adhesive to a second surface destined to comprise asecond interface between said second member and said intermediatemember; contacting said first member to said intermediate member viasaid first adhesive to form said first interface; contacting said secondmember to said intermediate member via said second adhesive to form saidsecond interface; and curing said first adhesive and said secondadhesive with said intermediate member remaining in a free state suchthat said intermediate member can move due to shrinkage of at least oneof said first adhesive and said second adhesive, wherein, after curing,said first member and said second member are fixed to said intermediatemember and therefore fixed to each other.